title: Factors associated with thiopurine non-adherence in patients with inflammatory bowel disease.
abstract: BACKGROUND
  Medication non-adherence seems to be a particular problem in younger patients with inflammatory bowel disease (IBD) and has a negative impact on disease outcome.
  
  
  OBJECTIVE
  To assess whether non-adherence, defined using thiopurine metabolite levels, is more common in young adults attending a transition clinic than adults with IBD and whether psychological co-morbidity is a contributing factor. We also determined the usefulness of the Modified Morisky 8-item Adherence Scale (MMAS-8) to detect non-adherence.
  
  
  METHODS
  Seventy young adults [51% (36) male] and 74 [62% (46) male] adults were included. Psychological co-morbidity was assessed using the Hospital Anxiety Depression Scale (HADS) and self-reported adherence using the MMAS-8.
  
  
  RESULTS
  Twelve percent (18/144) of the patients were non-adherent. Multivariate analysis [OR, (95% CI), P value] confirmed that being young adult [6.1 (1.7-22.5), 0.001], of lower socio-economic status [1.1 (1.0-1.1), <0.01] and reporting higher HADS-D scores [1.2 (1.0-1.4), 0.01] were associated with non-adherence. Receiver operator curve analysis of MMAS-8 scores gave an area under the curve (95% CI) of 0.85 (0.77-0.92), (P < 0.0001): using a cut-off of <6, the MMAS-8 score has a sensitivity of 94% and a specificity of 64% to predict thiopurine non-adherence. Non-adherence was associated with escalation in therapy, hospital admission and surgeries in the subsequent 6 months of follow up.
  
  
  CONCLUSIONS
  Non-adherence to thiopurines is more common in young adults with inflammatory bowel disease, and is associated with lower socio-economic status and depression. The high negative predictive value of MMAS-8 scores <6 suggests that it could be a useful screen for thiopurine non-adherence.
authors.affiliation: Centre for Digestive Diseases, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
authors.forename: J R
authors.initials: JR
authors.lastname: Goodhand
authors.forename: N
authors.initials: N
authors.lastname: Kamperidis
authors.forename: B
authors.initials: B
authors.lastname: Sirwan
authors.forename: L
authors.initials: L
authors.lastname: Macken
authors.forename: N
authors.initials: N
authors.lastname: Tshuma
authors.forename: Y
authors.initials: Y
authors.lastname: Koodun
authors.forename: F A
authors.initials: FA
authors.lastname: Chowdhury
authors.forename: N M
authors.initials: NM
authors.lastname: Croft
authors.forename: N
authors.initials: N
authors.lastname: Direkze
authors.forename: L
authors.initials: L
authors.lastname: Langmead
authors.forename: P M
authors.initials: PM
authors.lastname: Irving
authors.forename: D S
authors.initials: DS
authors.lastname: Rampton
authors.forename: J O
authors.initials: JO
authors.lastname: Lindsay
mesh_terms: D000328:Adult; D000367:Age Factors; D001007:Anxiety / Q000150:complications; D003430:Cross-Sectional Studies; D003863:Depression / Q000150:complications; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy*; D008297:Male; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D011687:Purines / Q000008:administration & dosage / Q000627:therapeutic use*; D012680:Sensitivity and Specificity; D012959:Socioeconomic Factors; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D007166:Immunosuppressive Agents; D011687:Purines